Finding Nemo 2: Nameless Creatures
Finding Nemo 2
Creatures With No Name
|Norfanz vessel, see full image slide show|
As Harvard professor of evolutionary biology, Andrew Knoll, remarked: " [For astrobiology] everything we know about life in the universe comes from life on Earth. In a sense, putting current diversity at peril for those who would like to understand biology as a planetary phenomenon is like burning a library."
To explore deep sea habitats and biodiversity in the Tasman Sea, a joint Australian-New Zealand research voyage carried leading Australian, New Zealand and other international scientists to uncover new marine species and habitats. The NORFANZ research voyage explored deep sea habitats around seamounts and abyssal plains around Lord Howe and Norfolk Islands through to northern New Zealand. The voyage collected biodiversity samples, DNA tissue samples, seabed habitat data, photographs and video on seamounts at depths between 200 meters and 1.2 kilometers, and surveyed free-swimming animals that live in the water masses above and around these seamounts. Australia’s National Oceans Office – the body responsible for developing and implementing Australia’s Oceans Policy – and the New Zealand Ministry of Fisheries supported the four-week voyage between 10 May and 8 June.
With cooperation from the National Oceans Office , the NASA-sponsored Astrobiology Magazine chronicles the scientific notes written by the researchers onboard. As the director of the Hayden Planetarium, Neil Tyson, wrote about the marvels of biodiversity: "I do not know whether biologists walk around every day awestruck by the diversity of life. I certainly do. On this single planet called Earth, there co-exist (among countless other life forms), algae, beetles, sponges, jellyfish, snakes, condors, and giant sequoias. Imagine these seven living organisms lined up next to each other in size-place. If you didn’t know better, you would be hard-pressed to believe that they all came from the same universe, much less the same planet".
The main goal of the summer expedition mirrored that sentiment: to provide baseline information on the, nature and potential vulnerability of these unique habitats and their biodiversity. The results will give scientists interested in biodiversity a much better understanding of the species that live on and around the deep seamounts and ridges throughout the Tasman Sea, many of which were new to science. The information will also enhance and contribute to international collaboration in oceans management.
Day 3: 14.00hrs, 12 May 2003.
Steaming at 14 knots.
Wind SW 5 knots; sea slight, SW swell 1m. Air temp 19.7 C, sea surface temp 20.0 C.
Last night we worked on fishes and invertebrates taken by the orange roughy trawl. Although catches were relatively small, we collected some valuable specimens, including at least two fish species new to New Zealand . The invertebrates are more difficult to identify on board, but our specialists tell me that we have collected a number of species new to New Zealand and to science.
|Vampire Squid, see full image slide show|
After midnight we changed gear to the heavily armoured, epi-benthic sledge nicknamed "Sherman". This is a rectangular metal box about 1 x 2m in size, built like a tank to sample very rough bottoms. This sledge is designed to sample invertebrates, sediment and rocks, which are collected in a net protected by a wire bag.
Sherman was operated down the slope in three tows similar to the path taken earlier by the trawl. A number of sponges, molluscs, echinoderms and prawns were collected. The sledge also captured some small rattail fishes and a rare slickhead.
After completing three Sherman tows we said goodbye to the New Zealand slope and headed northwest towards the remote Norfolk Ridge. It will take over 20 hours steaming to reach our first seamount station. On the way we shall shoot the mid-water trawl down to about 1200m depth in order to sample the deep pelagic fauna – that weird and rarely seen group of fishes, prawns and squids. These are usually black or red in colour, some with bizarre shapes and often with rows of flashing blue, red or green lights on the body.
Upon reaching the seamount we shall shoot the mid-water trawl again to compare this fauna with that of the open ocean. The differences will help us assess the effects of the adjacent seamount on the pelagic life.
Meantime we have a long steam in front of us, which will allow both watches to catch up on some sleep, to consolidate our records, and prepare for tomorrow’s operations.
Day 4: 11.00hrs, 13 May 2003.
Wind SE 20 knots; sea moderate, SW swell 1-2m. Air temp 19.8 C, sea surface temp 21.0 C.
We are presently steaming slowly northwards mapping the seabed in order to locate the top of a seamount that we plan to sample today. Published charts of the area are unreliable due to the small amount of survey work carried out here. Therefore we are building up our own accurate bottom charts using a system called swath mapping that uses a special type of echo sounder. Once the area has been mapped we can assess the safest track along which to shoot the sampling gear. Also we can see how hard and rough the seabed is and so select an appropriate trawl or sledge to work on that type of bottom. If the gear works as planned we shall have a very busy next 24 hours, sorting and identifying the samples.
|The onboard library of reference species for comparison with nightly trawls, see full image slide show|
Last night we carried out a mid-water trawl down to 1295m depth over a bottom depth of 3600m. The net was towed for 1.5 hrs at a speed of 2.5 knots. This is much slower than usual for this type of net, but was necessary because the cod-end has a special fine liner inside that would blow out at a faster speed. The liner is needed to retain the numerous small fishes, squids and prawns that inhabit these depths.
This was our first shot with this net and liner and we were not sure how well it would work at a slow towing speed because there is a risk of crossing the trawl doors and tangling the net. However, as it happened it worked very well and captured some scientifically valuable specimens as described below.
By Andrew Stewart, Te Papa scientist
It is 03.15hrs and we have just finished an extremely busy five hours identifying, photographing and recorded the last catch which consisted of shrimps, squids, octopods and fishes. At this station we used a 5-mesh mid-water trawl designed to sample creatures that live in open water. These animals spend their whole lives without seeing either the surface 100′s of meters above or the sea floor 100′s of meters below. They are truly swimming in "inner space".
Because the creatures we are after are so fragile and delicate, it took over an hour to haul the net back up to the surface – haul too fast and the water pressure would damage them. When the trawl was finally emptied, the catch would have filled a shopping bag. This gives some idea of the low density of life at these mid-water depths. However what a great mix of weird and wonderful animals we collected.
It has taken a team of five fish experts over five hours to sort and identify the 35 fish species sampled. Some have exotic names such as viperfish, snipe eel and hammerjaw. Others are very rare and have no name; two species are new records for the region.
Day 5: 11.00hrs, 14 May 2003.
Wind SE 28 knots; sea moderate, SW swell 2-3m. Air temp 20.1 C, sea surface temp 21.2 C.
By Clive Roberts, Te Papa scientist
We had a rough night — the sea was rough and the seabed was rough. Together these caused problems that were in turn rough on the ship’s officers who were trying to locate suitable tracks to tow, and to the crew who staunchly mended the broken gear. The scientists also had a rough night, all passionately hoping for some good samples to work on but instead becoming seasick, and our watch leaders who had to continually modify sampling plans to suit the tough conditions.
|Sea Mount geography around Lord Howe, see full image slide show|
The first part of the night was spent trying to locate a seamount that was mapped but was not in fact present. Later we found some pinnacles that were not mapped but were unfortunately too small to sample. When we did find an area that appeared to be okay on the echo sounder – not being too rough or sloping – during the first shot our dredge became stuck fast, then during the second shot Sherman our heavy-duty dredge was badly damaged.
In this area the bottom is very hard and deceptively flat but fractured with fissures and valleys that are nearly impossible to tow our bottom gear over. This uncharted area is a real challenge, so we have moved closer to Norfolk Island to operate on some softer seabed that hopefully will not destroy our sampling gear.
Yes, we did find better ground to work. However we continued to hang up the gear on the bottom. The orange roughy trawl became fast but broke free when we reversed over the top of it, then we used the beam trawl for the first time but the beam broke in half (which it is designed to do). Due to these hang-ups neither set of gear worked well so catches were small.
Nevertheless, we still managed to sample 3-4 boxes of fishes, including two species new to science. One is a distinctive grenadier or whiptail about 80cm long caught at about 650m depth that our specialists reckon is closely related to one off Japan and to another off New Zealand. This attractive fish has distinctive saddles across the body, a brown back and blue-green sides, and a striped anal fin.
The other new species is a pelagic fish that was picked up as the net was being hauled. This small dragonfish is less than 7 cm long, has a chin barbel with a light organ at the tip, but also has a light organ with filaments at the tip of the enlarged first ray of the pectoral fin.
Hopefully more specimens of the colourful grenadier and the unusual dragonfish will be taken in the next hauls.
|Norfanz deck filled with a catch, see full image slide show|
The Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the New Zealand National Institute of Water and Atmospheric Research Ltd (NIWA) are providing scientific support for the voyage. The NORFANZ voyage will use NIWA deep-sea research vessel, the R.V. Tangaroa (NORFANZ).
The expedition received considerable interest from scientists worldwide. Twenty four scientists from more than eleven research organisations will be represented onboard, including staff of CSIRO, Hobart; Museum Victoria; the University of Tasmania; Australian Museum; Queensland Museum; Northern Territory Museum; NSW State Fisheries; Te Papa, Wellington; National Institute of Water and Atmospheric Research, New Zealand; Institute de Recherche pour le Développement, Noumea; Natural History Museum, Paris; and California Academy of Sciences, San Francisco.